Overview of Anesthesia Machines
Introduction
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The anesthesia machine has been developed over time from a basic gas delivery apparatus to an integrated system of components used to provide a safe anesthetic.
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It is the most important piece of equipment in the operating room.
Supply Pipeline and Cylinder Gas
- Oxygen (O2), air, and nitrous oxide (N2O) are provided from two sources:
- Central pipeline supply
- Gas cylinders mounted on the back of the machine.
Color Coding Standard
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Gas tanks and the pressure hoses are color coded.
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The US color-coding standard differs from some colors used internationally:
- O2 = green
- Air = yellow
- N2O = blue
Flowmeters
- The flow meters on the anesthesia machine display the flow of the specified gas in liters per minute.
- Flow meters can be either manual or mechanical.
Vaporizers
- The purpose of a vaporizer is to convert the volatile anesthetic medication from a liquid to a set concentration of gas for delivery to the patient.
Carbon Dioxide Absorber
- The carbon dioxide (CO2) absorber is a critical part of the anesthesia machine that reduces the amount of exhaled CO2 that is inhaled by the patient.
Oxygen Flush Valve
- The oxygen flush valve delivers high-pressure high-flow oxygen to the common gas outlet from either the tank or pipeline.
Breathing Circuit
The breathing circuit is the critical connection
between the anesthesia machine and the patient.
Scavenging
- Scavenging systems remove the waste anesthetic gases from the operating room.
- This helps reduce exposure to nitrous oxide and halogenated anesthetic agents, which are potentially hazardous gases.
Ventilator
- A critical aspect of the practice of anesthesiology is the ability to ventilate patients.
- Anesthesia machines integrate the ventilator and its various controls and alarms.
Monitors
- Monitors form a critical connection between the
- patient,
- the anesthesia machine,
- and the anesthesia provider.
Summary
- The anesthesia machine is a critical component of the anesthesia work environment.
- These devices have grown in complexity and now often include:
- Not only the components necessary to deliver gas flows and anesthetic agents
- But come bundled with sophisticated ventilators and monitoring equipment.